Which risk increases when Song dynasty cannons use cast-iron?

💡 Explanation

Rapid crack propagation increases because cast iron, lacking ductility, experiences catastrophic brittle failure, initiating from stress concentrations during gunpowder explosion due to Griffith's crack theory; therefore structural barrel integrity diminishes, rather than the other options involving chemical stability or external forces.

• Which outcome arises when inadequately compacted terrace soils in Andean agriculture experience heavy rainfall?
• Which consequence occurs when a ship's sextant mirror darkens because of prolonged exposure to humid salt air?
• Which mechanism limited the standardization of medieval cast iron cannons?
• Which outcome increases when ancient chinampa agriculture lacked weeding?
• Which mechanism allowed Alhazen (Ibn al-Haytham) to improve the accuracy of stellar altitude measurements with his dioptra?
• Which limitation constrained practical surveying using al-Khwarizmi's algebraic techniques during the 9th century?